• 제목/요약/키워드: Repetitive strain

검색결과 83건 처리시간 0.029초

반복적인 골프 스윙으로 인한 노쪽손목굽힘근 힘줄의 파열 (Flexor Carpi Radialis Tendon Rupture due to Repetitive Golf Swing)

  • 이상철;고성훈;장진혁;안재기
    • Clinical Pain
    • /
    • 제18권2호
    • /
    • pp.107-110
    • /
    • 2019
  • Flexor carpi radialis (FCR) muscle is located in the forearm anteriorly that runs through a synovial fibro-osseous tunnel in the forearm. We described a case of FCR tendon rupture due to repetitive overuse injury. A 55-year-old man, right-hand dominant, presented with right forearm pain and swelling which started 3 days ago while playing amateur golf. Focal tenderness and bruising over volo-ulnar region of the right forearm were examined. Plain radiographs showed soft tissue edema around lesion area and no detectable fracture. Ultrasonography showed multiple hypoechoic lesions suspected as hematoma of the flexor muscle group. After done magnetic resonance imaging, he was diagnosed with rupture of FCR tendon at proximal origin and strain of flexor digitorum superficialis and palmaris longus muscle. He received compressive dressing and restriction of wrist range of motion for three weeks. Two months later, remaining traces of lesions were observed at the follow-up ultrasonography and the pain disappeared.

Detection of Mycobacterium leprae by Nested PCR Targeting M. leprae-Specific Repetitive Element (RLEP) Sequence

  • ;;;;;이혜영
    • 대한의생명과학회지
    • /
    • 제13권1호
    • /
    • pp.33-38
    • /
    • 2007
  • The aim of this work was to validate a rapid and an accurate method for detecting Mycobacterium leprae in clinical specimens using nested PCR targeting M. leprae-specific repetitive element (RLEP) sequence. The primers were derived from the RLEP sequence which yield a 272 bp outer product and a 230 bp inner product. The specificity and the sensitivity of the nested PCR were compared with those of single PCR for detecting M. leprae using DNAs isolated from reference strain and various species of Mycobacterium. The results showed that the sensitivity of the nested PCR was about 100 to 1,000 times higher than that of the single PCR and also showed that both the single and the nested PCR were highly specific to M. leprae. Subsequently, the usefulness of the single and nested PCR was evaluated with clinical samples isolated from leprosy patients. The number of positive detections by the single and the nested PCR with a total of 20 specimens from leprosy patients were 9 (45%) and 20 (100%), respectively. The results clearly showed that nested PCR has highest sensitivity in detecting M. leprae from clinical specimens. Therefore, nested primers targeting RLEP sequence developed in this study seems to be useful to detect the presence of M. leprae.

  • PDF

강한 지진하중하에서 강부재의 정량적인 손상 모델 (Quantitative Damage Model of Steel Members under Severe Seismic Loading)

  • 박연수;박선준
    • 한국강구조학회 논문집
    • /
    • 제10권3호통권36호
    • /
    • pp.339-353
    • /
    • 1998
  • 본 논문에서는 정량적인 지진 손상모델의 유도를 위해 먼저 지진 반복하중하에서 구조물 및 그들 요소에 대한 기존의 손상 모델들을 체계적으로 정리한 후 문제점을 평가하였다. 또한, 강한 지진과 같은 심한 반복가력을 받는 강구조 부재에 대한 파괴기준을 묘사하였으며, 강부재에 대한 새로운 지진 손상도 평가방법을 제안하였다. 이 손상모델은 극저 사이클 하중하에서 강부재에 대한 일련의 실험과 수치해석 연구로부터 얻어진 것이다. 본 연구에서 극저 사이클 하중은 큰 소성변형 영역안에서 5~20 사이클의 반복하중을 의미한다. 제안된 내진 손상평가 방법은 변형이 가장 심하게 집중된 단면에 있어서 국소 변형율의 이력에 초점을 맞추어 유도되었다.

  • PDF

강합성 교량에 설치된 압전소자의 전력발생효과 분석 (Analysis of Electric Power Effect of Piezoelectric Element on Steel-concrete Composite Bridge)

  • 김상효;정치영;정하민;안진희
    • 한국강구조학회 논문집
    • /
    • 제22권5호
    • /
    • pp.411-420
    • /
    • 2010
  • 교량은 주행차량에 의하여 지속적이며 반복적인 변형에너지가 발생하며, 이러한 교량의 변형에너지를 압전소자를 이용하여 전기에너지로 변환 할 수 있다. 하지만 압전소자를 구조물에 부착하여 구조물의 운동에너지를 전기에너지로 변환하여 사용하기 위해서는 구조물에 작용하는 하중 및 하중에 따라 압전소자에서 발생하는 변형률 관계 등이 제시되어야 압전소자를 합리적으로 적용할 수 있는 가능성을 평가할 수 있다. 따라서 본 연구에서는 압전소자를 교량 구조물에 적용하였을 때 발생하는 전압을 평가하기 위하여 강교량을 모사한 강합성 거더 교량 실험체를 제작하고 교량의 하중효과 등을 고려한 하중을 재하하고 이에 따라 압전소자에서 발생되는 전압을 평가하고 압전전압의 제안식과 실험결과를 비교하였다.

Biodegradation of Organochlorine Insecticide Endosulfan by the Fungus Eutypella sp. KEF-1

  • Lee, Jung-Bok;Park, Sang-Yeul;Shin, Kee-Sun;Jeon, Chun-Pyo;Kim, Jang-Eok;Kwon, Gi-Seok
    • 한국환경농학회지
    • /
    • 제30권2호
    • /
    • pp.202-208
    • /
    • 2011
  • BACKGROUD: ${\alpha}$- and ${\beta}$- Endosulfan isomers of endosulfan, an endocrine disrupting chemical, are widely used cyclodiene organochlorine pesticide in worldwide, and it has widespread application in agriculture and can contaminate river-system as runoff from soil or aerial deposition METHOD AND RESULTS: In this study, an attempt was made to isolate an endosulfan degrading fungus from endosulfan-polluted agricultural soil. Through repetitive enrichment and successive subculture in media containing endosulfan and its metabolites as the sole carbon source, a fungus designated KEF-1 was isolated. Based on phylogenetic analysis, strain KEF-1 was assigned to the genus Eutypella. Also, the ITS (internal transcribed spacer) sequences of KEF-1 were submitted to GenBank under accession number EF581006. In potato dextrose broth containing 8 ${\mu}g$/mL endosulfan, strain KEF-1 completely degraded the endosulfanin 12 days. CONCLUSION: These results suggested that Eutypella sp. KEF-1 has potential as a biocatalyst for endosulfan bioremediation

가공경화를 이용한 고강도 Al 6056 볼트의 생산 공정설계 (Manufacturing Process Design of High Strength Al 6056 Bolts by Strain Hardening Effect)

  • 박종수;김유빈;김승우;김하성;안규희;박정섭;강종훈
    • 소성∙가공
    • /
    • 제30권4호
    • /
    • pp.165-171
    • /
    • 2021
  • This study was conducted on the manufacturing method of high-strength aluminum bolts. We obtained the displacement-load information by tensile test of the Al 6056 raw material and the T6 heat-treated material and calculated the precise flow stress and fracture limit using repetitive finite element analysis for before and after heat treatment. We designed a multi-stage forging process for T6 heat-treated material, and calculated that the accumulated damage value does not exceed fracture limits by finite element method. We produced the prototype forgings without any harmful defects such as cracks and folding occurring. Bolts made of T6 heat treated material show 9.6%higher tensile strength than T6 heat treated material after wire drawing.

정적 및 반복하중 시의 주관절 Tendon의 파괴 물성치 측정 (Failure Properties of Common Tendon Origins at the Human Elbow after Static and Repetitive Loading)

  • 한정수;이관희;유재영
    • 대한의용생체공학회:의공학회지
    • /
    • 제19권4호
    • /
    • pp.393-401
    • /
    • 1998
  • 임상학적인 관찰에 따르면, 반복적인 하중에 의하여 뼈/건의 접합부분에 발생하는 부분적인 파손은 병리학적인 변화를 유발시킴으로 인하여 주관절의 상골과염(Epicondylitis)으로 발전시킬 수 있는 주요한 원인으로 간주되고 있다. 반복적인 하중이나 정적인 하중 하에서의 주관절에 위치한 신전건 및 굴곡건의 기계학적인 물성치와 파괴양상은 지금까지 잘 알려져 있지 않다. 본 연구에서는 상골과염과 직접적인 관계가 되는 신전건 및 굴곡건의 기계학적인 물성치인 파괴강도, 반복하중의 회수와 변형율(Strain)간의 연관관계 및 반복하중에 있어서의 생체조직학적 변화의 향상, 특히 파괴의 진행양상을 관찰하였다. 적용하중의 속도에 따르는 신전건 및 굴곡건의 파괴강도의 통계학적인 차이는 보이지 않고 있으나, 파괴강도에 있어서 신전건은 1199.0 N/$cm^2{\pm}$388.8, 굴곡건 1922.0 N/$cm^2{\pm}$764.4로, 굴곡건이 신전건에 비하여 1.6배 정도 크게 나타났으며, 상호간의 파괴강도에 있어서 통계학적인 차이가 있음을 보여주고 있다.(p<0.05). 조직학적 관찰에 의하면, 반복하중 하에서 뼈/건의 접합부분 특히 Uncalcified Fibrocartilage 부분에서 분리가 시작되었으며, 이는 상골과염을 발생시키는 주요생체조직부분이라는 것을 시사하고 있다.

  • PDF

반복하중을 받는 철근콘크리트보의 전단피로손상거동 (Shear Damage Behavior of Reinforced Concrete Beams under Repetitive Fatigue Loadings)

  • 오병환;한승환;유영;조재열
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
    • /
    • pp.633-638
    • /
    • 1997
  • This study was performed to investigate the fatigue behaviour and fatigue damage process of RC structures under repeated load. Especially, the behavior of RC beams subjected to flexure-shear force has been focused. The test results show that the deflections of beam and the strains of longitudinal steels and stirrups under cyclic loads increase with constant rate, and these increases depend on diagonal crack openings and strain increases. The present study provides useful data for the analysis of damage accumulation of reinforced concrete beams under repeated loadings.

  • PDF

Isolation and Characterization of 2-Methyl-4-Chlorophenoxyacetic Acid-Degrading Bacteria from Agricultural Soils

  • Cho, Seung-Hee;Ka, Jong-Ok
    • Journal of Applied Biological Chemistry
    • /
    • 제42권2호
    • /
    • pp.57-61
    • /
    • 1999
  • Seven numerically dominant 2-methyl-4-chlorophenoxyacetic acid (MCPA)-degrading bacteria were isolated from agricultural soils. The isolates utilized the herbicide MCPA as a sole carbon source, producing significant biomass in MCPA mineral medium. They exhibited diverse herbicide degradation capabilities, but most of them grew very slowly in mineral medium containing herbicide. The chromosomal DNA patterns of the isolates obtained by polymerase chain reaction amplification of repetitive extragenic palindromic sequences were distinct from each other. One isolate, SH3, which was identified as Sphingomonas species by fatty acid methyl ester analysis, was able to degrade 5 different phenoxyacetic acid herbicides within 4 days. This strain contains two plasmids, and the smaller one has a crucial role in herbicide degradation. MCPA treated into agricultural soils without indigenous MCPA-degraders persisted for a long time, but the application of the isolate SH3 resulted in rapid decline of MCPA concentration in the soil.

  • PDF

마그네슘 판재의 고온 물성치 실험 (Experiments for Material Properties of Magnesium Metal Sheet at Elevated Temperatures)

  • 최의근;이상욱
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2009년도 춘계학술대회 논문집
    • /
    • pp.378-381
    • /
    • 2009
  • In this study, the repetitive loading-unloading tensile tests with AZ31B magnesium sheet metal have been conducted under various elevated temperatures to check out how the Young's moduli of the sheets evolve during the plastic deformation. The loading-unloading tests have been carried out at every 1% of strain increment. With the tested results, some damage parameters of magnesium sheets based on the Lemaitre's continuum damage theory could be calculated at room temperature, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$ and $250^{\circ}C$. It has been shown that the critical damage parameters obtained in all temperature conditions are within the range of 0.12 to 0.18.

  • PDF